if you have a PC with Windows XP/Vista:
Start --> All Programs --> Accessories --> System Tools --> Character Map
from there you should be able to scroll down and see the different character options (Greek, Cyrillic, Arabic, etc). Click once and the lowercase mu, and push the copy button on the lower right hand side of the Character Map box. That symbol should now be copied to your clipboard and you can paste into anything (Internet browser, Word, OpenOffice, Notepad, whatever it is):
μ